[Contrast-enhanced ultrasound in differential diagnosis of focal liver lesions].

AIM

To continue studying the features of visualization of focal liver lesions by using of contrast-enhanced ultrasound (CEUS).

MATERIAL AND METHODS

A retrospective analysis included 106 patients with morphologically confirmed benign liver tumors and metastases (MTS). Patients were divided into groups regarding morphological criteria: focal-nodular hyperplasia (FNH) - 22 patients, hemangiomas - 26, hepatocellular adenoma (HCA) - 15 and 43 patients with liver MTS. All patients underwent multiparametric ultrasound examination with CEUS.

RESULTS

Characteristic signs of FNH are early contrasting in the arterial phase (AF) and significantly different 'contrasting onset in focus' in comparison with hemangiomas (p<0.001), HCA and MTS (p<0.05). Specific signs: 'spokes of the wheel' symptom and advanced contrast accumulation (96%), 'center-to-edge' filling (86%). There was no contrasting in AF in 42% of patients with hemangiomas. Specific signs are 'peripheral nodular exacerbation' (92%) and 'edge-to-center' filling (76%). WASH-OUT sign is not typical. HCA is characterized by complete (100%) and intensive (80%) centripetal filling. WASH-OUT sing was detected in 6 (40%) patients (p<0.001 for 'wash-out onset' and p<0.005 for 'maximum wash-out time' in comparison with MTS). We did not find specific types of vascular pattern. The most important differential sign of MTS was WASH-OUT sign (100%). Me of 'wash-out onset' sign was 40 (35-56) seconds. Specific signs: 'black hole' symptom - 50% of patients, asymmetric vascular pattern - 39.5%, circumferential exacerbation (27.9%) and hypoperfusion zones in AF (32.6%).